(1) Field of the Invention
The present invention relates to a substrate cleaning apparatus and a substrate processing apparatus including the substrate cleaning apparatus.
(2) Description of Related Art
A substrate processing apparatus is used to apply a variety of processing to substrates such as semiconductor substrates, substrates for use in liquid crystal displays, plasma displays, optical discs, magnetic discs, magneto-optical discs, photomasks, and other substrates.
In the substrate processing apparatus, a substrate held by a spin chuck, for example, is subjected to cleaning processing. An example of the spin chuck includes an edge holding type spin chuck that holds the outer peripheral edge of the substrate (see, for example, JP 2009-260033 A).
The spin chuck described in JP 2009-260033 A is mainly composed of a spin motor, a rotating shaft, a spin plate, a shield plate and a plurality of holders.
The rotating shaft is provided to extend downward from the inside of the spin motor, and the disc-shaped spin plate is attached to the lower end of the rotating shaft. A disc-shaped shield plate is attached to the lower surface of the spin plate. The plurality of holders are attached to the periphery of the spin plate so as to extend downward from the spin plate. The upper surface of the substrate comes closer to the lower surface of the shield plate with the substrate being held by the plurality of holders. The spin plate rotates around a vertical axis, causing the substrate to rotate horizontally. In this state, the back surface of the substrate is cleaned by a brush or the like. After the completion of the back surface cleaning processing, the substrate rotates at high speed. Thus, cleaning liquid adhering to the substrate is shaken off, so that the substrate is dried.